RE: Tsagantsabian age

["Tim Donovan" <msdonovan66@hotmail.com>]

> From: "Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>
> To: <msdonovan66@hotmail.com>
> Subject: RE: the last stegosaur
> Date: Tue, 30 Jul 2002 08:45:22 -0400
>
> > >In answer to your question, though, Wuerhosaurus was once
> > considered to be
> > >the latest-occuring stegosaur, but new (as you note) new data
> > indicate that
> > >it could be older than the Wealden stegosaur material.
> >
> >
> >   What new data?  Shuvalov wrote that Tsagantsabian sediments had 
> already
> > begun to accumulate by the end of the late Jurassic, which
> > suggests an early
> > EK age for Wuerhosaurus. Does other new data confirm this?
> >
>
> The Shuvalov work IS the new data (compared to older work).


   I notice there are at least two units of EK age underlying the 
Lianmuqin-presumably the basis for the old estimate of a late EK age for 
Wuerhosaurus. Shuvalov showed that Tsagantsabian datable materials from 
Mongolia have yielded ages of about 130 Ma, so maybe Wuerhosaurus, from the 
correlative Lianmuqin, was neither very early nor late in the EK but of c 
Hauterivian age. I don't know if that's older than the Wealden- probably 
coeval.




>             Thomas R. Holtz, Jr.
>                 Vertebrate Paleontologist
> Department of Geology           Director, Earth, Life & Time Program
> University of Maryland          College Park Scholars
>                 College Park, MD  20742
> http://www.geol.umd.edu/~tholtz/tholtz.htm
> http://www.geol.umd.edu/~jmerck/eltsite
> Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
> Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796




_________________________________________________________________
Join the world?s largest e-mail service with MSN Hotmail. 
http://www.hotmail.com